e19397 Background: Cemiplimab is a high-affinity, human, hinge-stabilized, monoclonal antibody that potently blocks the interactions of programmed cell death-1 (PD-1) with programmed cell death ligand-1 (PD-L1) and PD-L2. In September 2018, cemiplimab-rwlc became the first systemic therapy approved by the US Food and Drug Administration for the treatment of patients with advanced CSCC ineligible for curative surgery or radiotherapy. In a single-arm Phase II study (NCT02760498), cemiplimab demonstrated substantial antitumor activity, durable responses, and acceptable safety profile in patients with advanced CSCC. The aim of this analysis was to evaluate the cost-effectiveness of cemiplimab in patients with advanced CSCC from a US payer perspective. Methods: A partitioned survival model was developed to assess the cost-effectiveness of cemiplimab versus historical standard of care (SOC). All inputs were identified based on a systematic literature review (SLR), which was supplemented by expert opinion where necessary. The clinical inputs for cemiplimab were based on the individual patient data from the cemiplimab Phase II trial, whereas for SOC, the analysis was based on a pooled analysis of single-arm clinical trials and retrospective studies evaluating chemotherapy and epidermal growth factor receptor inhibitors (cetuximab, erlotinib, and gefitinib) identified via the SLR (6 of the 27 included studies). Overall survival and progression-free survival were extrapolated over a lifetime horizon using parametric functions consistent with guidance from the National Institute for Health and Care Excellence Decision Support Unit. Costs were included for drug acquisition, drug administration, management of adverse events, subsequent therapy, disease management, and terminal care. Unit costs were based on published 2019 US list prices. Results: In the base case, cemiplimab versus SOC resulted in an incremental cost-effectiveness ratio (ICER) of $99,024 per quality adjusted-life year (QALY), where incremental costs and QALYs were $372,425 and 3.76, respectively. At a willingness-to-pay threshold of USD $150,000 per QALY, the probabilistic sensitivity analysis suggests a 91% probability that cemiplimab is cost-effective when compared to SOC. Scenario analyses resulted in ICERs ranging from $90,326 to $147,944. Conclusions: Compared with historical SOC, cemiplimab is a cost-effective use of US payer resources for the treatment of advanced CSCC and is expected to provide value for money.
